Cameron McCormack:
> SVG 1.1 technically does not apply the opacity property to <tspan> and
> other text content child elements. Implementations seem to support
> this, though, so I will make the spec allow this unless there are any
> objections.
Similarly, pointer-events technically doesn't apply to <tspan>s either.
This is because it (and opacity) say that it applies to the "graphical
elements", and that term includes <text> but not the text content child
elements.